首先弄一个带宽高的服务器：




```
https://www.aliyun.com/minisite/goods?userCode=28kqeewo&accounttraceid=70263e6b6d5141c4807d779046c7ae45qyor
```

然后参考：

[https://www.cnblogs.com/6324/p/12516047.html](https://www.cnblogs.com/6324/p/12516047.html)

![在这里插入图片描述](/static/img/images/00268.png)

注意这个：

![在这里插入图片描述](/static/img/images/00269.png)

![在这里插入图片描述](/static/img/images/00270.png)

![在这里插入图片描述](/static/img/images/00271.png)

windows10如何使用：

[https://www.kuaidaili.com/doc/using/win10/](https://www.kuaidaili.com/doc/using/win10/)

CentOS 搭建服务器 阿里云使用

（1）用POST方法传输；





（2）用requests.post的json参数传是可以的，直接给，requests.post自动转成json；

（3）用requests.post的data参数传也是可以的，给成json字符串；

（4）POST的请求头部可给可不给，会自动识别，但是接口有自己特殊的请求头部的时候一定得给，比如下图：

![在这里插入图片描述](/static/img/images/00310.png)

写法1
```python
import requests
res = requests.post(url="http://0.0.0.0:8001/items/1",
                    json={
                        "name": "Foo",
                        "description": "A very nice Item",
                        "price": 35.4,
                        "tax": 3.2,
                    },
                    headers={"Content-Type": "application/json; charset=UTF-8"}
                    )
print(res.text)
```

写法2
```python
import json
import requests
res = requests.post(url="http://0.0.0.0:8001/items/1",
                    data=json.dumps({
                        "name": "Foo",
                        "description": "A very nice Item",
                        "price": 35.4,
                        "tax": 3.2,
                    }),
                    headers={"Content-Type": "application/json; charset=UTF-8"}
                    )
print(res.text)
```

Python requests post application/json

# 四种POST 请求方式：





[https://imququ.com/post/four-ways-to-post-data-in-http.html#toc-2](https://imququ.com/post/four-ways-to-post-data-in-http.html#toc-2)

Content-Type: application/x-www-form-urlencoded  最原始表单，参数单一，不能传文件。

Content-Type:multipart/form-data  改进后的表单，能传文件。

Content-Type: application/json  倾向于传json，json规范导致前后端传数据都喜欢用这个，数据生产和消费简单。

# FastAPI 中如何支持

[https://fastapi.tiangolo.com/zh/tutorial/schema-extra-example/](https://fastapi.tiangolo.com/zh/tutorial/schema-extra-example/)

把函数参数改为Body解析即可，而不是FORM解析。

```python
# -*- coding:utf-8 -*-
import traceback
import uvicorn
from typing import Optional
from fastapi import Body, FastAPI
from pydantic import BaseModel
from fastapi.middleware.cors import CORSMiddleware
app = FastAPI(
    title='FastAPI',
    description='FastAPI',
    version='1.0.0',
    docs_url='/docs',
    redoc_url='/redocs',
)
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)
class Item(BaseModel):
    name: str
    description: Optional[str] = None
    price: float
    tax: Optional[float] = None
@app.post("/items/{item_id}")
async def update_item(
        item_id: int,
        item: Item = Body(
            ...,
            example={
                "name": "Foo",
                "description": "A very nice Item",
                "price": 35.4,
                "tax": 3.2,
            },
        ),
):
    results = {"item_id": item_id, "item": item}
    return results
if __name__ == '__main__':
    uvicorn.run('fastapia:app', host='0.0.0.0', port=8001, reload=False, debug=False, workers=1)
```

# PostMan 测试

修改请求头

![在这里插入图片描述](/static/img/images/00319.png)

写raw的原生json字符串

![在这里插入图片描述](/static/img/images/00320.png)


```python
import requests
requests.post(url="http://0.0.0.0:8001/items/1",
              json={
                  "name": "Foo",
                  "description": "A very nice Item",
                  "price": 35.4,
                  "tax": 3.2,
              },
              )
```

FastAPI python content-type: application/json

参考:[https://blog.csdn.net/haveanybody/article/details/86494063](https://blog.csdn.net/haveanybody/article/details/86494063)





# 基础

cv2 打开图片，tensor的shape是（im_height, im_width, channel），BGR格式。**cv2.imread返回的是numpy.ndarray张量。**

pillow 打开图片，RGB格式。Pillow读出来的是PIL.Image.Image对象。

# 打开图片与保存图片

```python
##PIL 读取、保存图片方法
from PIL import Image
img = Image.open("eee.jpg")
img.save("eee_result.jpg")
##cv2 读取、保存图片方法
import cv2
img = cv2.imread("eee.jpg")
cv2.imwrite("eee_result.jpg", img)
##图片文件打开为base64
import base64
def img_base64(img_path):
    with open(img_path, "rb") as f:
        base64_str = base64.b64encode(f.read())
    return base64_str
```

# CV2中的  BGR转RGB

```python
from matplotlib import pyplot as plt
import cv2
img = cv2.imread("eee.jpg")
cv2.imwrite("eee_result.jpg", img)
imgrgb = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
plt.imshow(imgrgb)
plt.show()
```

# PIL CV2 的相互转换

```python
## PIL转cv2
import cv2
from PIL import Image
import numpy as np
img_rgb = Image.open("eee.jpg")
img_bgr = cv2.cvtColor(np.asarray(img_rgb), cv2.COLOR_RGB2BGR) # 成为cv2的numpy.ndarray
```

```python
## PIL转cv2
import cv2
from PIL import Image
img_bgr = cv2.imread("eee.jpg")
img_rgb = Image.fromarray(cv2.cvtColor(img_bgr, cv2.COLOR_BGR2RGB)) # 成为Pillow的PIL.Image.Image对象
```


# PIL base64 的相互转换

```python
##PIL转base64
import base64
from io import BytesIO
from PIL import Image
def pillow_to_base64(image):
    img_buffer = BytesIO()
    image.save(img_buffer, format='JPEG')
    byte_data = img_buffer.getvalue()
    base64_str = base64.b64encode(byte_data)
    return base64_str
# example
img = Image.open("eee.jpg")
print(pillow_to_base64(img))
```

```python
##PIL转base64
import base64
from io import BytesIO
from PIL import Image
def base64_to_pillow(base64_str):
    image = base64.b64decode(base64_str)
    image = BytesIO(image)
    image = Image.open(image)
    return image
# example
with open("eee.jpg", "rb") as f:
    base64_str = base64.b64encode(f.read())
print(base64_to_pillow(base64_str))
```

# CV2 base64 的相互转换

```python
# cv2 转 base64
import base64
import cv2
def cv2_to_base64(image):
    base64_str = cv2.imencode('.jpg', image)[1].tostring()
    base64_str = base64.b64encode(base64_str)
    return base64_str
# example
image = cv2.imread("eee.jpg")
print(cv2_to_base64(image))
```

```python
# base64 转 cv2
import base64
import numpy as np
import cv2
from PIL import Image
from io import BytesIO
def base64_to_cv2(base64_str):
    imgString = base64.b64decode(base64_str)
    nparr = np.frombuffer(imgString, np.uint8)
    image = cv2.imdecode(nparr, cv2.IMREAD_COLOR)
    return image
# example
with open("eee.jpg", "rb") as f:
    base64_str = base64.b64encode(f.read())
print(base64_to_cv2(base64_str))
```


# FastAPI中bytes 转CV2

```python
img = cv2.imdecode(np.frombuffer(file, dtype=np.uint8), cv2.IMREAD_COLOR)
```

# FastAPI中uploadfile  转CV2

```python
img = cv2.imdecode(np.fromstring(fileb.file.read(), np.uint8), cv2.IMREAD_COLOR)
```


# CV2 numpy  转成 字节流（open("file.jpg",'rb')）

参考：[https://blog.csdn.net/sinat_29957455/article/details/107208432](https://blog.csdn.net/sinat_29957455/article/details/107208432)

```python
img = cv2.imread("lpr1.png")
# 对数组的图片格式进行编码
success, encoded_image = cv2.imencode(".jpg", img)
# 将数组转为bytes
f = encoded_image.tobytes()
```

cv2 pillow base64 bytes uploadfile 图片文件之间的转换 FastAPI

#  FastAPI 服务





下面是代码，

`@app.post("/files/")` 路由让我们可以传文件。

`@app.post("/uploadfiles/")`路由让我们可以传多个文件。

需要保证：

（1） uvicorn.run中写的是文件名：app名，确保自己的文件名。

（2）`# python 3.8   pip install fastapi uvicorn python-multipart`

```python
# -*- coding:utf-8 -*-
import traceback
from typing import List, Optional, Union
import uvicorn
from fastapi.middleware.cors import CORSMiddleware
from fastapi import FastAPI, File, Form, UploadFile
import cv2
import numpy as np
app = FastAPI(
    title='FastAPI Tutorial',
    description='FastAPI教程',
    version='1.0.0',
    docs_url='/docs',
    redoc_url='/redocs',
)
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)
@app.post("/files/")
async def alg_file(
        fileb: UploadFile = File(...),
        token: str = Form(...)
):
    try:
        img = cv2.imdecode(np.fromstring(fileb.file.read(), np.uint8), cv2.IMREAD_COLOR)
        return {
            "token": token,
            "filename": fileb.filename,
            "content_type": fileb.content_type,
            "size": img.shape
        }
    except:
        traceback.print_exc()
        return -1
@app.post("/uploadfiles/")
async def create_upload_files(files: List[UploadFile] = File(...)):
    return {"filenames": [file.filename for file in files]}
@app.post("/filesper/")
def filesper(
        file: Optional[bytes] = File(None),
        fileb: Optional[UploadFile] = File(None),
        filepath: Optional[str] = Form(None),
):
    try:
        if file:
            img = cv2.imdecode(np.frombuffer(file, dtype=np.uint8), cv2.IMREAD_COLOR)
            return {
                "size": img.shape,
                "style": "bytes"
            }
        if fileb:
            img = cv2.imdecode(np.fromstring(fileb.file.read(), np.uint8), cv2.IMREAD_COLOR)
            return {
                "filename": fileb.filename,
                "content_type": fileb.content_type,
                "size": img.shape,
                "style": "UploadFile"
            }
        if filepath:
            return {
                "str": filepath,
                "style": "str"
            }
    except:
        traceback.print_exc()
        return -1
if __name__ == '__main__':
    uvicorn.run('yolo5fastapi:app', host='0.0.0.0', port=8001, reload=False, debug=False, workers=1)
```


#  requests 测试

## requests 单一文件上传

测试上传一个图片文件：

```python
import requests
url = "http://0.0.0.0:8001/files/"
with open("/home/kevin_xie/yifeinfs/pycharm_k/yolov5_v2/kevin/picture/realcamera.jpg", "rb") as f:
    res = requests.post(url=url, data={"token": "sdas"}, files={"fileb": f}, timeout=None)
    print(res.json())
```

返回：

```python
{'token': 'sdas', 'filename': 'realcamera.jpg', 'content_type': '', 'size': [720, 1280, 3]}
```

## requests 多个文件上传

注意给文件参数的方式，元组和列表均可，可自由尝试。
```python
import requests
url = "http://0.0.0.0:8001/uploadfiles/"
with open("/home/kevin_xie/yifeinfs/pycharm_k/yolov5_v2/kevin/picture/realcamera.jpg", "rb") as f:
    res = requests.post(url=url, files=[("files", f), ("files", f), ("files", f)], timeout=None)
    print(res.json())
```

Python fastapi requests 传文件方式 上传文件 上传多个文件 UploadFile模板方式 上传图片

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